My Garden
common cowparsnip
Heracleum maximum
Heracleum maximum, commonly known as cow parsnip, is a large, herbaceous, flowering plant in the carrot family (Apiaceae). It is native to North America and parts of Asia. It features large, compound umbels of small white flowers and large, deeply lobed leaves. While the plant can be attractive, it's important to handle it with care, as its sap can cause phytophotodermatitis, a skin reaction that results in blisters and burns when exposed to sunlight. Some people consume parts of the plant after careful preparation but this should not be attempted without expert guidance.
| Category | Details | |
|---|---|---|
| Plant Type | Perennial plant | |
| Medicinal Usage | Medicinal Usage | |
| Duration to maturity | 1 year to harvest | |
| Estimated Plant Lifespan | 2 years lifespan | |
| Toxic to humans | Toxic to humans | |
| Sun Requirements | 4-6 hours direct sunlight (Partial Sun) | |
| Pollination | Method: animal Notes: Pollinated by a variety of insects, especially flies and bees. | |
| Watering Requirements | Frequency: Keep soil consistently moist, especially during dry periods. | |
| Humidity Requirements | Level: moderate | |
| Cleaning Requirements | Wear gloves and protective clothing when handling this plant to avoid skin contact with the sap. Deadhead spent flowers to prevent self-seeding if not desired. Be cautious when working around cow parsnip on sunny days, as the combination of sap and sunlight can cause severe skin reactions. | |
| Temperature Range | Min: -20°C Max: 30°C | |
| Alternative Names | Heracleum sphondylium f rubriflorum, Heracleum sphondylium turugisanense, Pastinaca lanata, Sphondylium lanatum, cow parsnip, American cowparsnip, Heracleum sphondylium lanatum, Heracleum lanatum, Heracleum douglasii, Heracleum inperpastum, Heracleum turugisanense, Indian celery, giant hogweed, Pushki |
Canada goldenrod
Solidago canadensis
Both thrive in similar moist meadow conditions and bloom around the same time, creating a vibrant display. Goldenrod can also attract beneficial insects which can help to pollinate cow parsnip.
common milkweed
Asclepias syriaca
Both prefer similar growing conditions and can compete for resources, especially space and nutrients in moist soils. Cow parsnip's large size can shade out milkweed, hindering its growth.
Parsnip webworm
The parsnip webworm (Depressaria pastinacella) larva creates webs around flower heads and feeds on the developing seeds, affecting seed production.
Steps:
- Sow seeds in fall or early spring directly into the ground or in pots.
- Cover seeds lightly with soil and keep moist.
- Germination can be slow and erratic.
Neem oil
Effective against parsnip webworm infestations.